Astronomers have now
measured of all of the CHNOPS elements in 150,000 stars across the
Milky Way, the first time such a large number of stars have been
analyzed for these elements.

"For the first time,
we can now study the distribution of elements across our
Galaxy," says Sten Hasselquist of New Mexico State University.

"The elements we
measure include the atoms that make up 97% of the mass of the
human body."

Astronomers with
the Sloan Digital Sky Survey made their
observations with the
APOGEE (Apache Point Observatory
Galactic Evolution Experiment) spectrograph on the 2.5m Sloan
Foundation Telescope at Apache Point Observatory in New Mexico.

This instrument
looks in the near-infrared to reveal signatures of different
elements in the atmospheres of stars.

Quote from Carl Sage.

Credit: Pinterest

While the
observations were used to create a new catalog that is helping
astronomers gain a new understanding of the history and structure of
our galaxy, the findings also,

"demonstrates a
clear human connection to the skies," said the team.

While humans are
65% oxygen by mass, oxygen makes up less than 1% of the mass of all
of elements in space. Stars are mostly hydrogen, but small amounts
of heavier elements such as oxygen can be detected in the spectra of
stars.

With these new
results, APOGEE has found more of these heavier elements in the
inner part of the galaxy.

Stars in the inner
galaxy are also older, so this means more of the elements of life
were synthesized earlier in the inner parts of the galaxy than in
the outer parts.

So what does that
mean for those of us out on the outer edges of one of the Milky
Way's spiral arms, about 25,000 light-years from the center of the
galaxy?

"I think it's
hard to say what the specific implications are for when life
could arise," said team member Jon Holtzman, also from New
Mexico State, in an email to Universe Today.

"We measure
typical abundance of CHNOPS elements at different locations, but
it's not so easy to determine at any given location the time
history of the CHNOPS abundances, because it's hard to measure
ages of stars.

On top of that,
we don't know what the minimum amount of CHNOPS would need to be
for life to arise, especially since we don't really know how
that happens in any detail!"

Jon Holtzman
added it is likely that, if there is a minimum required abundance,
that minimum was probably reached earlier in the inner parts of the
Galaxy than where we are.

The team also said
that while it's fun to speculate how the composition of the inner
Milky Way Galaxy might impact how life might arise, the SDSS
scientists are much better at understanding the formation of stars
in our Galaxy.

"These data
will be useful to make progress on understanding Galactic
evolution," said team member Jon Bird of Vanderbilt University,
"as more and more detailed simulations of the formation of our
galaxy are being made, requiring more complex data for
comparison."

Sloan Foundation 2.5m
Telescope

at Apache Point
Observatory.

Credit: SDSS.

"It's a great
human interest story that we are now able to map the abundance
of all of the major elements found in the human body across
hundreds of thousands of stars in our Milky Way," said Jennifer
Johnson of The Ohio State University.

"This allows us
to place constraints on when and where in our galaxy life had
the required elements to evolve, a sort 'temporal Galactic
habitable zone'".

The catalog is
available at the SDSS website, so take a look for
yourself at the chemical abundances in our portion of the galaxy.